[TenTec] Notch Filters and Speech Processing in Orion V2 Code

[ROBERT CARROLL]

Merle-

Thanks for the insights.  I have been talking with Paul Clinton about the V2
Speech Processing as well, and I know they are working on it.  Although I am
primarily a cw op, I use SSB enough to be very aware that the processor
seems to lose control at times, even though the processing is set at a very
low level compared to V1 settings.  Though I do not normally use VOX, I did
turn it on for the first time since loading V2 the other day and found that
I could beat on the mike with a spoon and not trip the vox at the settings
of the V1 loads.  In fact I had to run the trip level down to zero before
VOX worked.  After inquiring, Paul confirmed this was an issue which is
being investigated.  Overall V2 works well on my 565 for cw, and the
firmware seems to have none of the glitches of V1.  I have had the sweep on
routinely--which I never dared to do with V1--with no problems.  I am hoping
the SSB issues will be cleared in the new release.

Bob W2WG

-----Original Message-----
From: tentec-bounces at contesting.com [mailto:tentec-bounces at contesting.com]
On Behalf Of Merle Bone
Sent: Thursday, August 10, 2006 5:23 PM
To: tentec at contesting.com
Subject: [TenTec] Notch Filters and Speech Processing in Orion V2 Code

Bill Tippet wrote:

  Just hours later I received a response
from K4JU Jack Burchfield, CEO of Ten-Tec:
"I understand your problem with the agc and notch and so does
Gary."
<details snipped>
"We have been working on possible solutions and have
not shelved it!  Will keep you in the loop."
............................................................................
...............

I have also been communicating with Jack Birchfield of a number of
areas of "performance degradation" and "bugs" in the Orion V2 code,
including the issue of the notch filters being outside the AGC loop - which
causes the notched signals to still pump the AGC and desensitize the
receiver.
We have exchanged a number of letters and he recently wrote:

"Notch etc: This is a bit of a problem. We would like to have a "clean-up"
filter after all
DSP. The gain and AGC causes some unwanted noise and the clean-up filter
removes
this noise. We tried to solve both that and the notch behind the AGC. So far
there is not
a clear cut solution and we feel that the filter is more important to more
operators. This
does not mean that we will not continue to search for a solution."

I wonder if the "clean-up filter" is required because of the redesign of the
Orion DSP modulator/demodulator
from a "filter method design" to a Weaver method design in the V2 code?
Maybe someone on the list understands this
change and the need for the clean-up filter - which was not in the Orion V1
code and - as best as I can see - 
is not missed?

I had also reported issues with the Speech Processing performance in the V2
code.
Jack Burchfield also commented:

"The speech processing has been changed and should be posted within a couple
of weeks. We
will continue  to communicate and at least let everyone know why we did some
of the 
things that are in question."

This certainly is good news. Hopefully we can get some of the Orion V2
issues resolved before the Omni-VII starts
to dominate the use of the DSP programming resources.

Merle - W0EWM





_______________________________________________
TenTec mailing list
TenTec at contesting.com
http://lists.contesting.com/mailman/listinfo/tentec